结晶硅微粉对KBJ元器件封装用EMC气孔的影响

以3种不同类型的结晶硅微粉为主要填料,环氧树脂为基体树脂,酚醛树脂为固化剂,通过调节3种结晶硅微粉的含量和比例,制备出3种不同的环氧模塑料(EMC)并用于封装KBJ元器件。采用激光粒度分析仪分析3种结晶硅微粉的粒径,毛细流变仪测试EMC粘度,万能测试机、恒温加热板测试其螺旋流动长度和凝胶化时间,并研究3种不同EMC对封装KBJ元器件中气孔的影响。     

表面贴装设备中的回转头技术

表面贴装技术(SMT)作为第四代组装技术,被誉为电子工业一场新的组装技术革命,它对改变传统的电子元器件和插装技术,对电子产品的薄型化、小型化、轻量化和多功能化,对电子装备的现代化和国民经济的发展,正在起着相当大的推动作用。回转头型SMT器件贴装设备通过利用多轴原理,与常规的贴装设备相比较时,可以显著地节省间隔时间,从而提高生产效率。     

高速双头点胶机Point5050

表面贴装技术(SMT)的产品生产过程中,遇到两面贴装或贴装与插装混装的工艺要求时,必不可少地要用到点胶装置,将专用粘着剂按指定位置涂覆于印刷电路板上,贴装元器件后加温固化,再进行后续焊接工艺。 日本TESCON公司生产的点胶机P-5050(参见照片1),是软件编程控制的“跑位式”点胶装置,装有传送系统,可连入生产线使用。     

TDK：迎接小型化趋势下的EMC挑战

便携式设备的小型化要求元器件和PCB在小型化高密度的方向上不断前进,EMC(电磁兼容)的性能成为考验系统稳定性的一个重要参考。而在诸如混合动力汽车、无线宽带网络应用和生活家电中,EMC解决方案面临的挑战也越来越多。     

浅析De-flash溶液pH值变化对EMC和导线架间分层的影响

在分析芯片内部分层不良的过程中发现使用N型EMC所生产的产品占据了所有分层不良的绝大多数。对使用N型EMC生产制程中从注胶模压到弯脚成形的每一个步骤完成后均对产品进行超声波探测（SAM）,发现去残胶制程（De-flash）最有可能导致芯片内部分层,而其他制程不会导致分层。EMC是由许多高分子树脂材料及各种添加剂组成,这...     

片式元器件市场走势

自20世纪80年代以来,随着电子元器件向小型化、复合化、轻量化、多功能、高可靠性、长寿命的方向变革,相继出现了各种类型的片式电子元器件(SMC/SMD),导致了第四代组装技术即表面贴装技术(SMT)的出现,在世界上引发了一场电子组装技术的新革命。     

国际国内片式元器件技术市场走势

自20世纪80年代以来,随着电子元器件向小型化、复合化、轻量化、多功能、高可靠、长寿命的方向变革,相继出现了各种类型的片式电子元器件(SMC/SMD),导致了第四代组装技术即表面贴装技术(SMT)的出现,在世界上引发了一场电子组装技术的新革命。     

SMD技术向高端的发展趋势

引言 电子整机在小型化、便携式、多功能、数字化以及高可靠、高性能方面的需求,进一步推动表面贴装型元器件(SMD)技术向集成化迅速发展。原有的单一功能片式元器件无论从尺寸或功能、性能、可靠性等均远远不能满足需求。SMD采用混合微电子技术,进一步向混合集成化发展,已成为必然趋势。其中应用最多的是低温共烧陶瓷(LTCC)技术、多芯片组件(MCM)技术以及球栅阵列(BGA)封装技术、芯片尺寸封装(CSP)技术。     

SABIC推出新型ULTEM 3473树脂,有助于5G基站中的射频滤波器实现高达40%的减重

全球多元化化工企业沙特基础工业公司(SABIC)今天推出其首款基于聚醚酰亚胺(PEI)树脂并适用表面贴装技术(SMT)的材料——ULTEM3473树脂。这款新产品旨在通过提供金属替代来应对5G基站小型化和轻量化的市场趋势。例如,ULTEM 3473树脂有助于将金属腔体滤波器的重量减轻高达40%。     

大型异型器件的装配考虑

前言 随着电子技术的不断发展，表面贴装技术也不断的趋向成熟，但人们无论对表面贴装的元器件，还是对实现表面贴装装配的设备都不断提出更高、更新的要求，以适应电子产品不断呈现的小型化、便携化和高可靠性的发展趋势。     

Design and fabrication of an IC encapsulation mold adhesion force tester

In integrated circuit (IC) packaging, when epoxy molding compound (EMC) is filling the mold cavity and cured in the mold, adhesion occurs in the interface between EMC and mold surface. Too large an adhesion force can damage an IC and lower the yield rate. However, there was no report showing how to measure the mold adhesion force. This paper described the design and fabrication of an automatic EMC adhesion force test instrument that will measure adhesion force between mold surface and EMC. By measuring the adhesion force, one can judge how much does a specific type of surface treatment help in reducing the amount of mold adhesion force. One can also use this instrument to determine what parameters are important for reducing the magnitude of adhesion force between EMC and mold surface.     

A New Approach in Measuring Cu–EMC Adhesion Strength by AFM

Copper–epoxy molding compound (Cu–EMC) interface is known to be one of the weakest interfaces in an electronic package exhibiting delamination during reliability test. Thiol compound which bonds readily and forms a self-assembly monolayer (SAM) with copper is proposed to improve interfacial adhesion between copper and EMC. Conventional adhesion evaluation involves force measurement in macro-scale. However, inconclusive or even contradictive results are common in those tests because of uncontrollable surface conditions such as contamination and, in particular, roughness. To eliminate the roughness effect and reflect the true chemical bonding condition, an Si wafer was used as a substrate in the experiments. This study involves the use of an atomic force microscope (AFM) in characterizing the nanoscale adhesion force in a Cu–SAM–EMC system. Findings were used as the criteria in selecting a SAM candidate. A thiol compound having a carbonyl group is shown to be the best adhesion promoter from the measurement. The nanoscale AFM results are shown to be consistent with the result of macroscopic shear tests. It has been demonstrated, with SAM treatment on a cleaned copper surface, that the fracture force between Cu–EMC samples is improved from 119 to 195N.     

Adhesion improvement of Cu-based substrate and epoxy molding compound interface by hierarchical structure preparation

For microelectronic industry, Cu-based substrate and epoxy molding compound (EMC) interface is inherently weak and most likely to delaminate, well-known as a major threat for integrated circuits (ICs) reliability. In this paper, hierarchical whisker-like oxide/Cu cone structure was for the first time to be fabricated by combining electroless plating with heat treatment methods to enhance the interface adhesion between Cu-based substrate and EMC. The surface morphology was characterized by scanning electron microscope (SEM). Result shows that the hierarchical whisker-like oxide/Cu cone film is fine, dense and uniform; Single Cu cone structure is about 3–5 μm in height and 1 μm in root diameter; a layer of whisker-like oxide grows perpendicularly to circular surface of Cu cone, with length ranging from tens to hundreds of nanometers. Adhesion strength between the as-prepared substrates and EMC were measured by button shear test. With consideration of oxidation caused by practical processes (e.g. wire bonding), the interface of EMC and porous oxide formed at 260 °C for 5 min was taken as standard sample, representative of practical interface. To further study the effect of whisker-like oxide and Cu cone solely on adhesion performance, whisker-like oxide, porous oxide/Cu cone were investigated as well. Button shear test results reveal that interfacial adhesion strength of EMC and whisker-like oxide, porous oxide/Cu cone, hierarchical whisker-like oxide/Cu cone are 85%, 110% and 162% higher than that of standard interface. Moreover, the mechanism for adhesion improvement was discussed by facture surface observation, failure path assumption and force–displacement curve analysis. Results show that interface of EMC and hierarchical whisker-like oxide/Cu cone exhibits brittle/ductile property with about 3–5 μm thick EMC left on the fracture surface, indicating cohesive failure caused by remarkable mechanical interlocking effect.     

电磁兼容缩尺比测试方法介绍

本文对电磁兼容缩尺比测试方法进行了介绍.该方法适用于大型多天线产品研制过程中的电磁兼容预测试,易于在产品成型之前发现解决其潜在的电磁兼容问题,节约成本,是大型多天线产品研制过程中及其必要的测试手段.     

Study on the Adhesion Between Epoxy Molding Compound and Nanocone-Arrayed Pd Preplated Leadframes

Since Au is used as the end finish on Pd preplated leadframes (Pd PPFs), the weak adhesion between the surface noble metal Au and the epoxy molding compound (EMC) often causes delamination and reduces the reliability of integrated circuit (IC) packages, which greatly limits the application of Pd PPFs. This paper reports on a novel application of arrays of nanocones prepared by a special electrodeposition method to improve the adhesion between the leadframe and EMC. Nanocone-arrayed structures greatly increase the area of the interface between the Pd PPF and the EMC. Shearing strength tests indicate that the adhesion between the EMC and nanocone-arrayed PPF is three to four times higher than that of the conventional PPF. Apart from increased interfacial area, the effect of a physical inlay may also increase the adhesion strength.     

航空通信系统试飞过程中的电磁兼容性评估

电磁兼容性(EMC)是航空电子产品的主要性能,也是实现系统功能的重要保证。试飞试验是按照预想实现一种思想而提供最终证据的在机载真实环境条件下进行飞行试验,并通过试飞数据分析结果评估系统效能,所以,EMC预测是航空电子系统试飞评估主要内容之一。论述了基于电磁拓扑(Electromagnetic Topology)理论分析的航空通信系统EMC评估方法,该方法已在航空通信系统试飞中被采用。     

环氧树脂对环氧模塑料(EMC)的性能影响分析

在环氧模塑料中,环氧树脂是环氧模塑料的基体树脂,也是环氧模塑料的主要原材料,起着将其他组分交联结合到一起的重要作用。环氧树脂作为环氧模塑料的胶粘剂,具有粘合性高、固化收缩率小、耐化学介质稳定性好、电绝缘性优良、工艺性能良好等特点。因此环氧树脂类型的选择及其性能对环氧模塑料的性能都有很大的影响。文章简单介绍了环氧树脂的分类、结构、作用及特点,主要探讨了不同结构环氧树脂对环氧模塑料的粘接性、稳定性、收缩率、电性能及机械性能等的影响。     

Analyses of the practical adhesion strengths of the metal/polymer interfaces in electronic packaging

There is a plethora of techniques to measure the adhesion strength of metal/polymer interfaces. However, the practical adhesion strength, which is the work done in separating the film from the substrate (or one film from another), is very sensitive to the test methods and the mechanical effects, such as the residual stress, thickness and mechanical properties of the layers, strain rate, and phase angle. Deriving intrinsic-adhesion properties of the interfaces, which are independent of such parameters, from the practical adhesion-strength measurements is a formidable task. In the present work, data from the three commonly used adhesion tests; pull-out, 90°-peel, and T-peel tests are compared with the intrinsic-adhesion properties of the interface, such as the interface-fracture toughness or the interface-fracture energy, and their implications are discussed. Material systems analyzed were Cu-based lead frame/epoxy-molding compound (EMC) and Cu/Cr/polyimide.     

Modified single cantilever adhesion test for EMC/PSR interface in thin semiconductor packages

We propose and implement an adhesion test configuration called “modified single cantilever adhesion test” (M-SCAT) that can be employed to determine the adhesion strength of epoxy molding compound (EMC) and photo solder resist (PSR) interface in thin semiconductor packages. The proposed M-SCAT method is optimal for quick and quantitative in-situ testing of the interface with strong adhesion as sample preparation and testing are simple while maintaining a low mode mixity at the crack tip. Detailed sample preparation and experimental testing to determine the critical load required for delamination are presented. A numerical procedure is followed to assess the stress and strain fields around the crack tip at the point of delamination, thus allowing for the J-integral method to be employed to determine the critical energy release rate. The proposed approach is carried out for two different EMC/PSR interfaces. The results show excellent repeatability, which allows for the test method to be used effectively to select the most ideal material set for given applications.     

全自动平衡机系统中的EMC研究

介绍了全自动平衡机系统的组成及体系结构,并结合系统的运行环境、运行效果要求分析了系统的电磁兼容性,从电磁干扰三要素(干扰源、噪声耦合路径和敏感设备)着手,提出了保障系统电磁兼容性的若干手段.在此基础上进行了电磁兼容测试,给出了试验结果及结果分析.试验及实践结果表明,全自动平衡机系统达到了电磁兼容性要求.